[Study on the Fast Testing Strategy for identifying the wild poliovirus I].

OBJECTIVE

To explore the Fast Testing Sstrategy (FTS) for wild poliovirus I (WP1).

METHODS

Epidemiological investigations were carried out on 671 students from WP1 epidemic areas in China. A set of real time RT-PCR assays, including panenterovirus testings (PE) assay, poliovirus serotypings (PS) assay and the assay distinguishing wild strain from vaccine strain of poliovirus I (DWV) were introduced into the screening program for WPV1 to replace the conventional RT-PCR, recommended by the China National Polio Laboratory (GNPL). Additionally, sensitivities of all the assays were assessed by poliovirus type I to III (Sabin stain) and the isolated WPV1.

RESULTS

(1) 33 non-poliovirus enterovirus (NPEV) cases were detected, with 16 polio vaccine-related cases including 5 polio I, 1 polio II, 3 polio III, 1 polio I + II, 4 polio I + III and 2 polio I + II + III. Three WPV1 cases were also detected in this study and confirmed by CNPL. (2) For polio virus vaccine strain, sensitivities of the set of real time RT-PCR assays ranged from 1 to 100 times than that of the in-house RT-PCR assay. The sensitivities of PE and PS assays for the detection of polio II were 100 times than that of the RT-PCR assay and the sensitivity of DWV assay used for the detection of polio I were 10 times than that of the RT-PCR assay. For WPV1, the sensitivity of three real time RT-PCR was 10 times hight than that of the RT-PCR assay.

CONCLUSION

The novel FTS for WPV1 suggested by this study would include PE, PS and DWV. It not only could greatly shorten the testing time but also more sensitive than the RT-PCR and suited for emergency detection for WPV1.